Guardrail base



FIG. 1 is a front perspective view of the claimed design.

FIG. 2 is a left-side elevation view thereof.

FIG. 3 is a right-side elevation view thereof.

FIG. 4 is a top plan view thereof.

FIG. 5 is a bottom plan view thereof.

FIG. 6 is a front elevation view thereof.

FIG. 7 is a rear elevation view thereof; and,

FIG. 8 is a rear perspective view of three examples of the claimed design supporting a guardrail.

The solid lines represent the bounds of the claimed design, whereas those features shown in broken lines, form no part of the claimed design. 

CLAIM I claim the ornamental design for a guardrail base, as shown and described. 